Aims: To report a series of benign ovarian seromucinous neoplasms, an uncommon and hitherto poorly described category of tumours included in the current 2014 World Health Organisation classification of tumours of the female reproductive organs.
Methods and results: We report the clinicopathological features of a series of 22 benign ovarian seromucinous neoplasms (cystadenomas and adenofibromas or admixtures). The neoplasms occurred in patients aged 32-83 years (mean = 62, median = 65.5) and involved the left ovary (n = 14), the right ovary (n = 6) or both ovaries (n = 2). There was a common association with endometrioid elements (endometrioid differentiation within the cystadenoma/adenofibroma and/or endometriosis) and other endometriosis-associated neoplasms.
Conclusions: We speculate that some of these represent benign ovarian endometrioid neoplasms with foci of mucinous and/or serous differentiation, while others represent true mixed neoplasms.
Keywords: endometrioid differentiation; endometriosis; ovary; seromucinous cystadenoma/adenofibroma.
© 2020 John Wiley & Sons Ltd.